1. Eelco van Beek Marjolijn Haasnoot
Adaptive Delta Management How to deal with the uncertainties involved in Sea Level Rise? The Dutch approach
Eelco van Beek
Marjolijn Haasnoot
European-American – Transatlantic Solutions to Sea Level Rise Adaptation
Norfolk, VA, 30 October 2013

2. Adaptive Delta Management – What’s new?
What is not new?
we have for centuries adapted our delta to changing conditions
but always in response to (near) disasters
New is:
we now want to anticipate the change (SLR-CC) or consider transitions
but these changes are uncertain
this requires new approaches and methods for problem analysis, policy analysis and management planning
Dealing with ‘fundamental uncertainties’ is the key issue of ADM:
“what to do and when to do it?”
“not too much, not too little”
“not too early, nor too late”

3. Sea Level Rise (SLR) – one of the uncertainties
Uncertainties we face in anticipating changes
SLR
Other climate change effects (e.g. higher peak discharges rivers)
Socio-economic changes
Subsidence (and our ability to stop or decrease the rate)
Perspective of society on how to manage the system
Events
SLR is actually the most certain of these uncertainties
is taken place, also without climate change
accelerated SLR, how fast?
Scenario approach
integrated scenario’s
tendency to focus on ‘the worst credible’

4. Perpectives in views and management styles
Based on Cultural Theory

5. Sea level rise: many scenarios

6. Now look who is talking….
Before long The Netherlands
will look like this
Al Gore, inconvenient truth
He didn’t mention that the Netherlands has the highest safety levels in the world:
1 : 10,000 years for flooding from the sea
1 : 1,250 years for flooding from rivers

7. The risk of climate change /
25 april 2017
Now we had a problem:
The risk of climate change /
sea level rise is not the flood hazard itself
but
The image that the Netherlands might
not be safe anymore for investments
Now that is a major risk!! 7 7

8. 2nd Delta commission First finding:
Scientists do not agree on magnitude of Climate change and sea level rise
Asked basically four questions
1. What is the maximum plausible SLR between now and 2100? (130cm)
2. Are we able to defend the Netherlands to that rise? (YES)
3. What will it cost? (1 B-EURO/yr)
4. Can we pay this? (YES)
OK, than that is what we will do, discussion closed

9. Working with transient scenario’s
Classical approach: end-point scenario’s (e.g. 2040, 2100)
But:
society changes also (perspectives, beliefs)
society learns and with that their response changes
Events are important triggers for changes
events in the Netherlands (near floods)
Al Gore
Katrina and Sandy
Wait or take action now?
Answer: combine the two
Use transient scenario’s in
which events and changing
perspectives are included

10. Adaptation Tipping Points (ATP)
Classical approach:
What if…(climate) changes according to scenario x?
Tipping point approach:
How much (climate) change can we cope with?
When will this occur?
tipping point
Spatial limits
Technical limits
Financial limits
Socially unacceptable
Governmental unacceptable
sell-by date of tipping point for each scenario

11. Example ATP, Rhine Meuse Estuary
the current
strategy for fresh water supply fails in the event of
a 35 cm sea-level rise, and that under a pessimistic
scenario, this could occur before 2050 (KNMI W+).
Under an optimistic scenario, the current water
supply strategy could hold until the end of the
century. The figure also shows that the strategy
of coastal defence through sand nourishment will
continue to be effective past the end of the century,
even if the most pessimistic (and low probability)
scenario of the Delta Committee is used (a 130 cm
rise in sea levels by 2100)
KNMI W 2050
KNMI G 2100
EEA, 2013

12. Determining ATP’s – Sell by dates
ATP depends on:
scenario’s (e.g. SLR, socio-economic developments)
occurrence of events (which are stochastic)
need to consider multiple transient scenario’s
perspectives
Many combinations are possible
computer can generate range of ATP

13. Moment of an ATP: Sell-by date policy actions based on ensemble of futures
Example: Waas case

14. Adaptation pathways
Sequence of policy actions to achieve targets under changing conditions

15. Adaptation pathways
Sequence of policy actions to achieve targets under changing conditions

16. Application in Delta Programme in the Netherlands
Experiencing pathways in a game-setting

17. Some lessons learned 1
Adaptation PATHWAYS provide insights into options, lock-in possibilities, and path dependencies.
Adaptation TIPPING POINTS help in assembling paths. However, the sell-by date interval can be large. 2
KEEP IT SIMPLE: screen or group actions (n=< 20). Concretize actions. One pathways map for one objective/area. 3
MONITORING plan and CONTINGENCY actions help to stay on track. Not for extremes. Autonomous adaptation of stakeholders can be important. 4 5
Pathways can be developed based on EXPERT JUDGEMENT or/and on MODELLING results.

18. Questions - Discussion